Emplement polymorphic in embedded

[giallon]

Add Polymorphic Support for Embedded Associations

Overview

Adds polymorphic embedded associations to embeds_one and embeds_many, allowing different document types to be embedded in the same association.

Features Added

1. Polymorphic Embedded Associations

• embeds_one: Embed different types in a single association
• embeds_many: Embed collections of mixed types
• Type information stored inside each embedded document as a type field

2. Hash Input with Type Key

Accept hashes with type key for convenient polymorphic initialization:

post = Post.new(media: { type: 'image', url: 'photo.jpg', caption: 'Sunset' })

• Uses snake_case class names ('image' → Image)
• Supports both symbol and string keys
• Raises ArgumentError if type key missing

3. Type Restrictions

Restrict allowed types by passing array to polymorphic:

class Post < CouchbaseOrm::Base
  embeds_one :media, polymorphic: ['Image', 'Video']
end

• polymorphic: false - Not polymorphic (default)
• polymorphic: true - Polymorphic, any type allowed
• polymorphic: ['Image', 'Video'] - Only specified types allowed
• Auto-converts snake_case to CamelCase ([:image, 'video'] → ['Image', 'Video'])

Examples

embeds_one

class Image < CouchbaseOrm::Base
  attribute :url, :string
  attribute :caption, :string
end

class Video < CouchbaseOrm::Base
  attribute :url, :string
  attribute :duration, :integer
end

class Post < CouchbaseOrm::Base
  embeds_one :media, polymorphic: true
end

# Using objects
post = Post.create!(media: Image.new(url: 'photo.jpg', caption: 'Sunset'))
post.media # => #<Image url: "photo.jpg", caption: "Sunset">

# Using hashes
post = Post.create!(media: { type: 'video', url: 'clip.mp4', duration: 120 })
post.media # => #<Video url: "clip.mp4", duration: 120>

embeds_many

class Article < CouchbaseOrm::Base
  embeds_many :attachments, polymorphic: ['ImageAttachment', 'VideoAttachment']
end

article = Article.create!(
  attachments: [
    { type: 'image_attachment', url: 'diagram.png' },
    { type: 'video_attachment', url: 'demo.mp4', duration: 90 }
  ]
)

article.attachments # => [#<ImageAttachment ...>, #<VideoAttachment ...>]

Files Changed

• embeds_one.rb - Polymorphic support
• embeds_many.rb - Polymorphic support
• embeds_one_spec.rb - 17 new tests
• embeds_many_spec.rb - 24 new tests
• associations.txt - Documentation with examples

Tests

• ✅ 111 tests passing (41 new polymorphic tests)
• ✅ Type validation with objects and hashes
• ✅ Persistence and retrieval
• ✅ Type switching
• ✅ Allowed types restrictions
• ✅ Error handling

Database Storage

Type information is stored inside each embedded document:

embeds_one:

{
  "_id": "post::123",
  "media": {
    "type": "Image",
    "url": "photo.jpg",
    "caption": "Sunset"
  }
}

embeds_many:

{
  "_id": "article::456",
  "attachments": [
    {
      "type": "ImageAttachment",
      "url": "diagram.png",
      "caption": "Architecture"
    },
    {
      "type": "VideoAttachment",
      "url": "demo.mp4",
      "duration": 90
    }
  ]
}

Benefits

• Clean, self-contained storage format
• Type information travels with the data
• No separate tracking fields needed
• Easy to understand and debug

Made changes.